Multiple concurrent bandwidth parts for a base station of a cellular network

ABSTRACT

Various arrangements for improving cell coverage are presented. A cellular network can define a first bandwidth part and a second bandwidth part to be implemented concurrently by a base station of the cellular network. The first bandwidth part and the second bandwidth part do not overlap and may be separated by a guard band. The first bandwidth part can have a greater bandwidth and greater sub-carrier spacing than the second bandwidth part. The cellular network can determine a first set of user equipment to use the first bandwidth part for communication with the base station and a second set of user equipment to use the second bandwidth part for communication with the base station. Communication with the first set of user equipment using the first bandwidth part and the second set of user equipment using the second bandwidth part may be performed.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No.16/518,866, entitled “Bandwidth Adjustment of Multiple ConcurrentBandwidth Parts for a Base Station of a Cellular Network”, filed on thesame day as this application, the entire disclosure of which is herebyincorporated by reference for all purposes.

BACKGROUND

A 5G cellular network base station can support multiple sub-carrierspacings (SCSs). While a higher SCS can have certain advantages, such aslow latency, a lower SCS can have other advantages, such as the basestation being able to provide coverage to a greater region.Additionally, battery life of the UE may be improved by less bandwidthand lower SCS being used for communication between the UE and basestation. Conventionally, when a single bandwidth part (BWP) is used forcommunication with UE, these factors may be weighed against each otherto determine a compromise configuration.

SUMMARY

Various embodiments are described related to a method for improving cellcoverage. In some embodiments, a method for improving cell coverage isdescribed. The method may comprise defining, by a cellular network, afirst bandwidth part and a second bandwidth part to be implementedconcurrently by a base station of the cellular network. The firstbandwidth part and the second bandwidth part may not overlap and may beseparated by a guard band. The first bandwidth part may have a widerbandwidth than the second bandwidth part. The first bandwidth part mayhave greater subcarrier spacing (SCS) than the second bandwidth part.The method may include determining, by the cellular network, a first setof user equipment to use the first bandwidth part for communication withthe base station and a second set of user equipment to use the secondbandwidth part for communication with the base station. The first set ofuser equipment may be distinct from the second set of user equipment.The method may comprise performing, by the base station, communicationwith the first set of user equipment using the first bandwidth part andthe second set of user equipment using the second bandwidth part.

Embodiments of such a method may include one or more of the followingfeatures: measuring, by a user equipment, a signal strength of a signalreceived from the base station and providing, by the user equipment, anindication of the signal strength to the base station. Determining, bythe cellular network, the first set of user equipment to use the firstbandwidth part for communication with the base station and the secondset of user equipment to use the second bandwidth part for communicationwith the base station may comprise, for the user equipment, selectingthe first bandwidth part or the second bandwidth part based on theindication of the signal strength. Selecting the first bandwidth part orthe second bandwidth part based on the indication of the signal strengthmay further comprise comparing the indication of the signal strength toa predefined threshold signal strength. The first bandwidth part may beselected in response to the indication of the signal strength beinggreater than the predefined threshold signal strength. The secondbandwidth part may be selected in response to the indication of thesignal strength being less than the predefined threshold signalstrength. The cellular network may use 5G New Radio (NR) radio accesstechnology (RAT). The method may further comprise monitoring, by thecellular network, bandwidth usage within the first bandwidth part andthe second bandwidth part and reallocating, by the cellular network, arelative amount of bandwidth within the first bandwidth part and thesecond bandwidth part based on the monitored bandwidth usage. The firstset of user equipment communicating with the base station using thefirst bandwidth part may experience lower latency than the second set ofuser equipment communicating with the base station using the secondbandwidth part. The second bandwidth part may provide coverage over agreater geographical area than the first bandwidth part.

In some embodiments, a cellular communication system is described. Thesystem may comprise a base station functioning as part of a cellularnetwork that communicates with a plurality of user equipment. The basestation may be configured to define a first bandwidth part and a secondbandwidth part to be implemented concurrently by the base station of thecellular network. The first bandwidth part and the second bandwidth partmay not overlap and may be separated by a guard band. The firstbandwidth part may have a wider bandwidth than the second bandwidthpart. The first bandwidth part may have greater subcarrier spacing (SCS) than the second bandwidth part. The base station may be configured todetermine a first set of user equipment of the plurality of userequipment to use the first bandwidth part for communication with thebase station and a second set of user equipment of the plurality of userequipment to use the second bandwidth part for communication with thebase station. The first set of user equipment may be distinct from thesecond set of user equipment. The base station may be configured toperform communication with the first set of user equipment using thefirst bandwidth part and the second set of user equipment using thesecond bandwidth part.

Embodiments of such a system may include one or more of the followingfeatures: the system may further comprise the plurality of userequipment. A piece of user equipment of the plurality of user equipmentmay be configured to measure a signal strength of a signal received fromthe base station and provide an indication of the signal strength to thebase station. The base station may be configured to determine the firstset of user equipment to use the first bandwidth part for communicationwith the base station and the second set of user equipment to use thesecond bandwidth part for communication with the base station maycomprise the base station being configured to, for the user equipmentinstance, select the first bandwidth part or the second bandwidth partbased on the indication of the signal strength. The base station beingconfigured to select the first bandwidth part or the second bandwidthpart based on the indication of the signal strength may further comprisethe base station being configured to compare the indication of thesignal strength to a predefined threshold signal strength. The firstbandwidth part may be selected in response to the indication of thesignal strength being greater than the predefined threshold signalstrength. The second bandwidth part may be selected in response to theindication of the signal strength being less than the predefinedthreshold signal strength. The cellular network may use 5G New Radio(NR) radio access technology (RAT) and the base station may be a gNodeB(gNB). The base station may be further configured to monitor bandwidthusage within the first bandwidth part and the second bandwidth part andreallocate a relative amount of bandwidth within the first bandwidthpart and the second bandwidth part based on the monitored bandwidthusage. The system may further comprise the plurality of user equipment.The first set of user equipment communicating with the base stationusing the first bandwidth part may experience lower latency than thesecond set of user equipment communicating with the base station usingthe second bandwidth part. The second bandwidth part may providecoverage over a greater geographical area than the first bandwidth part.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of variousembodiments may be realized by reference to the following figures. Inthe appended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 illustrates an embodiment of how sub-carrier spacing (SCS) may beselected for a cell of a cellular network.

FIG. 2 illustrates an embodiment of a cellular system 200 in which abase station communicates with multiple UEs.

FIG. 3 illustrates an embodiment of a cellular base station usingmultiple bandwidth parts to communicate with different sets of UE.

FIGS. 4A and 4B illustrate embodiments of multiple bandwidth partsallocated for use concurrently with a base station.

FIG. 5 illustrates an embodiment of a method for improving coverage of acellular network base station by concurrently using multiple bandwidthparts.

FIG. 6 illustrates an embodiment of a bandwidth adjustment transitionperformed for a base station and the UE communicating with the basestation.

FIG. 7 illustrates an embodiment of a method for transitioning abandwidth allocation of a base station.

DETAILED DESCRIPTION

A base station can be configured to divide available channel bandwidthfor communication by the base station (BS) into multiple bandwidth partsthat are used by the BS concurrently for communication with differentpieces of user equipment (UE). For UE located relatively close to the BS(e.g., that receive a high level of signal strength from the BS), the UEmay be assigned to use a first bandwidth part (BWP). The first BWP mayhave a greater bandwidth than a second BWP. The first BWP may havehigher subcarrier spacing and, thus, latency may be decreased. For UElocated relatively far from the BS (e.g., that receive a relatively lowlevel of signal strength from the BS), the UE may be assigned to use asecond BWP. The second BWP may have a lower bandwidth than the firstBWP. The second BWP may have lower subcarrier spacing and, thus, latencymay be greater than when the first BWP is used; however, the second BWPcan have a smaller bandwidth than the first BWP. By virtue of thebandwidth of the second BWP having a smaller bandwidth, resulting insmaller search part for UE, the power usage at the UE to search for itsscheduled data in the receive band and for transmitting to BS may bedecreased (and, thus, battery life may be increased).

When network traffic using a particular BWP increases above a definedthreshold, the BWP on which high traffic is being detected by the basestation may have its bandwidth increased by the base station. The otherBWP may have its bandwidth decreased by the base station, thus moredynamically allocating bandwidth based on the amount of traffic. In someembodiments, each UE may be provided with up to four BWP definitions. Ofthe up to four BWP definitions, only one BWP definition is used by a UEat a given time. When a base station determines to transition from usingfirst and second BWP definitions to third and fourth BWP definitions,the transition may involve first transitioning the BWP that is to bedecreased in bandwidth. Once all relevant UE are using the BWPdefinition that is smaller in bandwidth, the other BWP definition may betransitioned to the BWP that uses the BWP greater in bandwidth. Furtherdefinition regarding such transitions is provided in relation to FIGS. 6and 7.

FIG. 1 illustrates an embodiment 100 of how sub-carrier spacings may beselected for a cell of a cellular network. A bandwidth part (BWP) can beunderstood as a subset of contiguous physical resource blocks on acarrier. A BWP defines the carrier bandwidth for communication with abase station. At any given time, a UE communicates using a single activeBWP for uplink communications and a another single active BWP fordownlink communications for a given cell. In FIG. 1, in order to achievegreater cell sizes (and thus provide coverage to a larger geographicregion), smaller SCS may be used. As a smaller SCS is used, latency maybe increased. As shown in block 101, for a large cell size, a BS mayemploy SCS of 15 KHz. For a medium sized cell, at lower frequencies, aSCS of 15 KHz or 30 KHz can be used, as indicated by block 102. Also,for a medium sized cell, at mid-frequencies, a SCS of 30 KHz can beused, as indicated by block 103. For small cells, blocks 104, 105, 106,and 107 illustrates possible SCS at different frequencies.

FIG. 2 illustrates an embodiment of a cellular system 200 in which a BScommunicates with multiple UEs. Cellular system 200 can include: UE 210;UE 215; BS 235 (which can include BS tower 220 and gNodeB 230); corecellular network 240; and BWP management system 250.

In some embodiments, cellular system 200 represents a 5G New Radio (NR)cellular system. In other embodiments, other forms of radio accesstechnology (RAT) may be used.

UE refers to a wireless computerized device that communicate with BS235. For instance, pieces of UE can be smart phones, cellular phones,laptop computers, tablet computers, gaming devices, smart home devices,IoT devices, or any other computerized device configured to use theappropriate RAT to communicate with BS 235. UE may also include one ormore access points (APs). An access point may provide network access toone or more other devices. For instance, some devices may be able tocommunicate wirelessly via Wi-Fi. The AP may communicate locally withdevices using Wi-Fi and communicate with BS 235 using a different RAT.As illustrated, two UEs, 210 and 215, are presented. It should beunderstood that BS 235 may communicate with many more UEs concurrently.For instance, hundreds of UEs may be served by BS 235 at a given time.

BS 235 may provide service to a particular cell of a cellular network.BS 235 may include BS tower 220 and gNodeB 230. Specifically, gNodeB 230may only be present if the cellular network is a 5G NR network. In otherembodiments, such as if a 4G network is used, an eNodeB may be present.A gNodeB or eNodeB can represent hardware that is connected to themobile phone network that communicates directly wirelessly with UE.Antennas may be arranged on BS tower 220.

Core cellular network 240 may be in communication with many basestations. Various processing functions may be provided directly by corecellular network 240, by gNodeB 230, or by a separate system incommunication with core cellular network 240 or gNodeB 230. Forinstance, BWP management system 250 may be separate from and incommunication with gNodeB 230. Alternatively, BWP management system 250may be incorporated as part of core cellular network 240 or gNodeB 230.BWP management system 250 can be part of network management (NM) orsystem-level Radio Resource Management (RRM).

BWP management system 250 may manage the amount of bandwidth assigned todifferent BWPs of a given BS at a time. BWP may dynamically alter the BWassigned to each BWP such that different traffic loads on each BWP canbe accommodated. BWP management system 250 may include one or morecomputer server systems.

FIG. 3 illustrates an embodiment 300 of a cellular BS using multiplebandwidth parts to communicate with different sets of UE. Such anarrangement can improve cell coverage by the BS. In embodiment 300, BS305 is located near the center of the cell. BS 305 can represent anembodiment of BS 235 of FIG. 2. BS 305 may communicate with UEs usingdifferent BWPs. BS 305 may use a first BWP to communicate (uplink ordownlink transmissions) with UE that are located relatively close to BS305. More precisely, signal strength measurements may be used todetermine which UEs are relatively close to BS 305.

UEs 311, 312, 313, and 314 are within region 310 in which a relativelystrong signal strength is received by each UE from BS 305. For each ofthese UEs, a first BWP definition may be used. The first BWP definitionmay define a relatively wide-band BWP. On the first BWP a first SCS maybe used. The SCS may be greater, to allow for lower latency, than asecond BWP.

UEs 315, 316, and 317 are within region 320 in which a relatively weaksignal strength is received by each UE from BS 305. For each of theseUEs, a second BWP definition may be used. The second BWP definition maydefine a relatively narrow BWP (compared to the first BWP). On thesecond BWP, a second SCS may be used that differs from the first SCS.The SCS may be smaller than used for the first BWP. Such an arrangementmay increase latency but may effectively increase the coverage of thecell of BS 305 by allowing for communication with UE experiencing alower signal strength from BS 305. Therefore, for example, if only alarger SCS was used, UEs 315, 316, and 317 may have been effectivelyoutside of communication range with BS 305. However, by a second BWPbeing defined that allows for communication using the smaller SCS, UEs315, 316, and 317 can effectively communicate with BS 305.

Whether the first BWP or the second BWP is used for communicationbetween the BS and a particular UE may be dependent on the signalstrength measured by the UE (or by the BS). Particularly, UE 313 maymove in direction 308. As UE 313 moves, the signal strength may drop andBS 305 may transition UE 313 from communicating using the first BWP tousing the second BWP. In some embodiments, this action is accomplishedby transmitting a definition of the second BWP to UE 313. In otherembodiments, UE 313 already has stored definitions of both the first andsecond BWPs; in such embodiments, BS 305 may transmit a message toconfigure UE 313 to activate the second BWP instead of the first BWP. Insome embodiments, the message may include a timer defining when thesecond BWP should be activated.

Similarly, UE 317 may move in direction 309. As UE 317 moves, the signalstrength may increase and BS 305 may transition UE 317 fromcommunicating using the second BWP to using the first BWP. In someembodiments, this action is accomplished by transmitting a definition ofthe first BWP to UE 317. In other embodiments, UE 317 already has storeddefinitions of both the first and second BWPs; in such embodiments, BS305 may transmit a message to configure UE 317 to activate the first BWPinstead of the second BWP.

As shown in FIG. 3, both the first and second BWP are being used tocommunicate with different UEs by BS 305 concurrently. Therefore, whileUE 311 is using the first BWP to communicate with BS 305, UE 316 isusing the second BWP to communication with BS 305. While the examples ofthis document are focused on two BWPs being defined and usedconcurrently by BS 305, it should be understood that greater than twoBWPs can be concurrently used by BS 305.

FIGS. 4A and 4B illustrate embodiments of multiple bandwidth partsallocated for use concurrently with a BS. In embodiment 400A of FIG. 4A,two BWPs with a guard band are illustrated. A first bandwidth part 420has a greater bandwidth than BWP 410. BWP 420 may use a first, wider SCSthan BWP 410. For instance, BWP 420 may use a SCS of 30 KHz while BWP410 uses a SCS of 15 KHz. The relative amount of bandwidth assigned toBWP 420 and BWP 410 may be based on the relative amount of UE trafficusing each BWP. Between BWP 420 and BWP 410, a guard band 415 may bepresent. Guard band 415 may be necessary to avoid inter-numerologyinterference because of different SCS being used on BWP 420 and BWP 410.

In embodiment 400B of FIG. 4B, again here, two BWPs with a guard bandare illustrated. A first bandwidth part 440 has a greater bandwidth thanBWP 430. BWP 440 may use a first, wider SCS than BWP 430. As compared toembodiment 400A, the relative amount of bandwidth assigned to BWP 420and BWP 410 has been adjusted to compensate for a heavy bandwidth usageof BWP 410 occurring. As detailed in relation to guard band 415, betweenBWP 440 and BWP 430, guard band 435 may be present to avoidinter-numerology interference because of different SCS being used on BWP440 and BWP 430.

Various methods may be performed using the systems and arrangementsdetailed in relation to FIGS. 1-3. Specifically, various methods may beperformed in order to permit multiple BWPs to be used concurrently by aBS to improve its coverage characteristics. FIG. 5 illustrates anembodiment of a method for improving coverage of a cellular network BSby concurrently using multiple bandwidth parts. Method 500 may beperformed using cellular system 200 of FIG. 2. More specifically, blocksof method 500 may be performed using a UE, BS, core cellular network,and/or a BWP management system.

At block 510, a first BWP and a second BWP may be defined and anindication of the BWPs may be provided to the UE. The first BWP and thesecond BWP do not overlap and both exist within the overall channelbandwidth for use by the cellular network. The first BWP and second BWPmay be defined to be used by a BS concurrently—therefore, some UEs willbe using the first BWP and other UEs will be using the second BWP. Block510 may be performed by the base station (e.g., gNodeB), a component ofthe core cellular network, or by a BWP management system that is incommunication with components of the cellular network. The first BWP mayhave: 1) a greater SCS than the second BWP; and/or 2) greater bandwidththan the second BWP (e.g., similar to embodiment 400A of FIG. 4A).Therefore, the second BWP may have 1) a smaller SCS than the first BWP;and/or 2) greater bandwidth than the first BWP (e.g., similar toembodiment 400A of FIG. 4A).

At block 520, a UE may make a signal strength measurement based onsignals received from the base station. The UE may transmit anindication of the measured signal strength to the base station. In otherembodiments, the BS may measure the signal strength of one or moresignals received from the UE.

At block 530, the signal strength measurement, made either by the UE orby the base station, may be compared with a stored threshold signalstrength value. The comparison of block 530 may be performed locally atthe UE or, if the signal strength measurements were transmitted to ormade by the base station, block 530 may be performed by the basestation. In some embodiments, the threshold signal strength may beadjusted to perform load balancing. That is, if a large number of UEsare either greater or less than the threshold, the threshold may beadjusted to achieve a different distribution of UEs being greater orless than the threshold.

For a given UE, at block 540, a determination may be made as to whetherthe signal strength measurement is greater than the threshold signalstrength value. This determination may be made at the UE or at the basestation. If greater than the threshold signal strength value, method 500may proceed to block 550. If less than the threshold signal strengthvalue, method 500 may proceed to block 570.

At block 550, the UE may be assigned to use the first BWP forcommunication. A message from the BS can include an instruction to theUE to use the first BWP of which it has a stored definition. The firstBWP may be used for uplink or downlink communications between the BS andthe UE. In some embodiments, a definition of the first BWP istransmitted to the UE that indicates the SCS to be used and the resourceblocks available for use as part of the first BWP.

At block 560, communication between the BS and the UE may be performedusing the first BWP. The UE may experience lower latency due to agreater SCS being used. Occasionally or periodically, method 500 mayreturn to block 520 to repeat signal strength measurements and reassesswhether the UE should be using the first BWP or the second BWP.

At block 570, the UE may be assigned to use the second BWP forcommunication. This may include a message containing an instruction toswitch to using the second BWP being transmitted to the UE by the BS.The downlink channel bandwidth and the uplink channel bandwidth each maybe divided into multiple BWPs. This second BWP may be used for uplink ordownlink communications, depending on whether the BWP is assigned foruplink or downlink communications. If the second BWP uses less bandwidththan the first BWP, less power may be needed by the UE to communicateusing the second BWP than the first BWP. In other embodiments,definitions of the first BWP and the second BWP are provided to the UE,but only one of the BWPs is indicated in a message from the BS to the UEto be activated.

At block 580, communication between the BS and the UE (e.g., uplinkcommunications) may be performed using the second BWP. The UE mayexperience higher latency due to a smaller SCS being used; however, theUE may experience longer battery life (if the second BWP is smaller inbandwidth than the first BWP). Further, since a smaller SCS is used, theUE may be able to communicate with the BS, whereas if only the first BWPwas available, the UE may not be able to successfully communicate withthe BS. Occasionally or periodically, method 500 may return to block 520to repeat signal strength measurements and reassess whether the UEshould be using the first BWP or the second BWP.

While some number of UE may be using the first BWP for communicationwith the BS, other UEs are using the second BWP for communication withthe BS. Therefore, the BS is simultaneously using two (or more) BWPdefinitions for communication with UE.

As detailed in relation to FIGS. 4A and 4B it is possible to usedifferent amounts of bandwidth for different BWPs. For instance, BWP 410may be determined to have insufficient bandwidth for the volume of datatransmissions and/or the number of UEs communicating using BWP 410.Therefore, a base station or some component of core cellular network240, may determine that the bandwidth of BWP 410 should be increased. Todo so, the amount of bandwidth of BWP 420 may need to be decreased and aguard band may need to be maintained between BWP 410 and BWP 420. SinceBWP 410 and BWP 420 use different subcarrier spacings, the cellularnetwork must first ensure that all UE use the proper guardband toprevent inter-numerology interference. Further detail regarding how atransition between bandwidth part definitions is provided in relation toFIGS. 6 and 7.

FIG. 6 illustrates an embodiment 600 of a bandwidth adjustmenttransition performed for a base station and the UE communicating withthe base station. The bandwidth adjustment of embodiment 600 can beperformed by a base station, such as BS 235. The total amount ofbandwidth to allocate may remain unchanged; however, the amount ofbandwidth using a particular SCS can be adjusted. In some embodiments,BS 235 may be instructed to perform the transition by core cellularnetwork 240. Initially, two BWPs (BWP 410 and BWP 420) having differentSCSs may be used by the base station for communication with UEs. Thebase station may determine to enlarge BWP 410 to be BWP 430. Therefore,BWP 410 and BWP 430 may have the same subcarrier spacing, but BWP 430has a greater allocated bandwidth.

In some embodiments, the bandwidth of BWP 430 is predefined. That is,only two predefined options may be possible: BWP 410 or BWP 430. Inother embodiments, the bandwidth of BWP 430 may be dynamic in that thebase station can customize the amount of bandwidth assigned to be partof BWP 430 depending on factors such as the amount of communicationtraffic attempting to use the BWP, and/or the number of UE using theBWP.

Initially, as indicated by BWP arrangement 601, a base station mayconcurrently have two active BWP definitions corresponding to BWP 410and BWP 420, which can be separated by a guard band. In BWP arrangement601, which corresponds to embodiment 400A of FIG. 4A, BWP 410 and BWP420 use different subcarrier spacings and, therefore, guard band 415between BWP 410 and BWP 420 is needed to prevent inter-numerologyinterference. As can be seen from FIG. 6, since BWP is to be decreasedin bandwidth, a portion of BWP 420 overlaps BWP 430, which has adifferent SCS. Therefore, to prevent inter-numerology interference, itmay be necessary for UEs to not be scheduled to communicate using BWP420 before UEs start communicating using BWP 430.

A first transition from BWP arrangement 601 to BWP arrangement 602 maybe performed. As part of the first transition, UEs may receive aninstruction to communicate using BWP 440 instead of BWP 420. In someembodiments, UE can be assigned four definitions of BWPs. Therefore, amessage may be received that deactivates a definition corresponding toBWP 420 and activates a BWP corresponding to BWP 440. In otherembodiments, a new definition of BWP 440 is transmitted to UE thatdeactivates or replaces the definition corresponding to BWP 420. In someembodiments, the message to use BWP 440 is provided to all UEcommunicating with the BS. Therefore, if a UE is communicating using BWP410, the UE may be unaffected by the change relating to BWP 420.

A period of time may elapse to ensure that communication between all UEand the base station occur on BWP 410 and BWP 440 as indicated in BWParrangement 602. Therefore, when BWP arrangement 602 is active, atemporary adequate guard band 610 is present.

A second transition from BWP arrangement 602 to BWP arrangement 603 maybe performed. As part of the second transition, UEs may receive aninstruction to communicate using BWP 430 instead of BWP 410. In someembodiments, UE can be assigned and store up to four definitions ofBWPs. Therefore, a message (or group of messages) may be received thatdeactivates a definition corresponding to BWP 410 and activates adefinition corresponding to BWP 430. In other embodiments, a newdefinition of BWP 430 is transmitted to UE that deactivates or replacesthe definition corresponding to BWP 410. The message to use BWP 430 isprovided to all UE communicating with the BS. Therefore, if a UE iscommunicating using BWP 440, the UE may be (at least initially)unaffected by the change relating to BWP 430.

Once the transition to BWP arrangement 603 is complete, the transitionprocess may be complete. The example of BWP arrangement 603 correspondsto embodiment 400B of FIG. 4B. As detailed in relation to FIG. 4B, BWP430 and BWP 440 operate using different SCS. The required guard band 435will be maintained to prevent interference among BWPs 430 and 440 due tothe different SCSs.

As indicated by transition arrow 604 and transition arrow 605, thetransitions are bidirectional. Therefore, BWP arrangement 603 can betransitioned to BWP arrangement 602, which, in turn, can be transitionedto BWP arrangement 601. Such transitions can be used to increase thebandwidth of BWP 440 and decrease the bandwidth of BWP 430 (such as inresponse to increased communication traffic on BWP 440 or decreasedcommunication traffic on BWP 430).

FIG. 7 illustrates an embodiment of a method 700 for transitioning abandwidth allocation of a base station as detailed in relation to FIG.6. Method 700 may be performed using cellular system 200 of FIG. 2. Morespecifically, blocks of method 700 may be performed using a UE, BS, corecellular network, and/or a BWP management system.

At block 705, a first BWP and a second BWP (or more BWPs) may be definedby a BS or a core cellular network in communication with the BS. Thedefinitions of the first BWP and the second BWP may indicate theportions of bandwidth allocated to each BWP. Defining the first BWP andthe second BWP can include transmitting definitions of the first BWP andthe second BWP to UEs communicating with the BS. Therefore, each UE mayreceive two (or more) BWP definitions. At a given time, only a singleBWP definition may be active (such as detailed in relation to method500).

At block 710, for some period of time (e.g., seconds, minutes, hours,days, weeks), the BS may communicate with UE using the first BWP and thesecond BWP having different SCSs. For example, referring to FIG. 2, UEmay communicate with the BS using different BWPs having different SCSsin order to increase power efficiency, range, and/or data throughput.

At block 715, the base station or a component of the core cellularnetwork may determine that either the first BWP or the second BWP hasinsufficient bandwidth for current communication conditions. Forinstance, a large number of UE may be communicating using a particularBWP or a large amount of data may be transmitted to the BS via theparticular BWP. The determination may be made by the BS or a componentof the core cellular network comparing a total number of UE using aparticular BWP and comparing to a stored threshold value. Thedetermination may be made by the BS or a component of the core cellularnetwork based on comparing an amount of data received on a particularBWP to a stored threshold value. In some embodiments, in addition to orin alternate to the number of UE using a particular BWP, or the amountof data being transmitted on a particular BWP being above a threshold,the determination may be based on the other BWP being underused (e.g.,data throughput below a stored threshold, and/or the number of UE usingthe underutilized BWP being below a stored threshold value).

At block 720, a third BWP and a fourth BWP may be defined by the BS or acore cellular network in communication with the BS. The definitions ofthe third BWP and the fourth BWP may indicate the portions of bandwidthallocated to each BWP. The third and fourth BWP definitions represent achange from the allocations of the first BWP and the second BWP. For thepurposes of this example, the first and third BWPs have a same first SCSand the second and fourth BWPs have a same second SCS that differs fromthe first SCS. The bandwidth of the first BWP may be increased bytransitioning to the third BWP definition (thus increasing the amount ofbandwidth). Therefore, the second BWP may be transitioned to the fourthBWP, thus decreasing the amount of bandwidth using the required SCS.

Defining the third BWP and the fourth BWP can include transmittingdefinitions of the third BWP and the fourth BWP to UEs communicatingwith the BS. Therefore, each UE may receive two additional BWPdefinitions. In some embodiments, blocks 705 and 720 may be performedtogether. That is, each UE may receive four BWP definitions as part of asingle message or group of messages. At a given time, a UE may have asingle active BWP from selected from a group that are permitted to beactive. At any particular time, the UE can only be using a single BWPdefinition for communication. In other embodiments, the third and fourthBWP definitions may be provided at a later time. In such embodiments, itmay be possible to customize the amount of bandwidth assigned to eachBWP based on the amount of network traffic.

At block 725, whichever of the first BWP or the second BWP that is beingtransitioned to less bandwidth may be transitioned. Such a transitionmay be similar to the transition indicated in FIG. 6 from BWParrangement 601 to BWP arrangement 602. For example, referring to FIG.6, the first transition can include transitioning UE from communicatingusing BWP 420 to BWP 440. Performing the transition can include either:an instruction being transmitted to UE by the BS that indicates a BWPdefinition that is to be used. All UE communicating with the BS mayreceive the instruction to transition, but only UE currently using theparticular BWP being transitioned may be affected.

At block 735, the BWP that is to be enlarged in bandwidth may beadjusted by the new BWP definition being used by each UE. For example,referring to FIG. 6, and the transition from BWP arrangement 602 to BWParrangement 603, each UE may use BWP 430. Referring to the example ofFIG. 6, following this second transition, BWP 430 may use a portion ofbandwidth previously used by BWP 420.

At block 740, for some period of time (e.g., seconds, minutes, hours,days, weeks), the BS may communicate with UEs using the third BWP andthe fourth BWP having different SCSs. Such communicate may occur suchthat different UE use different BWPs (having different SCSs) communicatewith the BS simultaneously. At some point in the future, another set oftransitions may be performed in order to reallocate bandwidth due tochanging needs of the cellular network.

The methods, systems, and devices discussed above are examples. Variousconfigurations may omit, substitute, or add various procedures orcomponents as appropriate. For instance, in alternative configurations,the methods may be performed in an order different from that described,and/or various stages may be added, omitted, and/or combined. Also,features described with respect to certain configurations may becombined in various other configurations. Different aspects and elementsof the configurations may be combined in a similar manner. Also,technology evolves and, thus, many of the elements are examples and donot limit the scope of the disclosure or claims.

Specific details are given in the description to provide a thoroughunderstanding of example configurations (including implementations).However, configurations may be practiced without these specific details.For example, well-known circuits, processes, algorithms, structures, andtechniques have been shown without unnecessary detail in order to avoidobscuring the configurations. This description provides exampleconfigurations only, and does not limit the scope, applicability, orconfigurations of the claims. Rather, the preceding description of theconfigurations will provide those skilled in the art with an enablingdescription for implementing described techniques. Various changes maybe made in the function and arrangement of elements without departingfrom the spirit or scope of the disclosure.

Also, configurations may be described as a process which is depicted asa flow diagram or block diagram. Although each may describe theoperations as a sequential process, many of the operations can beperformed in parallel or concurrently. In addition, the order of theoperations may be rearranged. A process may have additional steps notincluded in the figure. Furthermore, examples of the methods may beimplemented by hardware, software, firmware, middleware, microcode,hardware description languages, or any combination thereof. Whenimplemented in software, firmware, middleware, or microcode, the programcode or code segments to perform the necessary tasks may be stored in anon-transitory computer-readable medium such as a storage medium.Processors may perform the described tasks.

Having described several example configurations, various modifications,alternative constructions, and equivalents may be used without departingfrom the spirit of the disclosure.

For example, the above elements may be components of a larger system,wherein other rules may take precedence over or otherwise modify theapplication of the invention. Also, a number of steps may be undertakenbefore, during, or after the above elements are considered.

What is claimed is:
 1. A method for improving cell coverage, the methodcomprising: defining, by a cellular network, a first bandwidth part anda second bandwidth part to be implemented concurrently by a base stationof the cellular network, wherein: the first bandwidth part and thesecond bandwidth part do not overlap and are separated by a guard band;the first bandwidth part has a wider bandwidth than the second bandwidthpart; and the first bandwidth part uses a first subcarrier spacing (SCS)that is greater than a second SCS of the second bandwidth part;assigning, by the cellular network, a first set of user equipment to usethe first bandwidth part and the first SCS for communication with thebase station based on a signal strength of each piece of user equipmentof the first set of user equipment being greater than a signal strengththreshold; assigning, by the cellular network, a second set of userequipment, distinct from the first set of user equipment, to use thesecond bandwidth part and the second SCS for communication with the basestation based on a signal strength of each piece of user equipment ofthe second set of user equipment being less than the signal strengththreshold; and performing, by the base station, communication with thefirst set of user equipment using the first bandwidth part and the firstSCS and the second set of user equipment using the second bandwidth partand the second SCS.
 2. The method for improving cell coverage of claim1, further comprising: measuring, by a user equipment, a signal strengthof a signal received from the base station; and providing, by the userequipment, an indication of the signal strength to the base station. 3.The method for improving cell coverage of claim 1, wherein the cellularnetwork uses 5G New Radio (NR) radio access technology (RAT).
 4. Themethod for improving cell coverage of claim 1, further comprising:monitoring, by the cellular network, bandwidth usage within the firstbandwidth part and the second bandwidth part; and reallocating, by thecellular network, a relative amount of bandwidth within the firstbandwidth part and the second bandwidth part based on the monitoredbandwidth usage.
 5. The method for improving cell coverage of claim 1,wherein the first set of user equipment communicating with the basestation using the first bandwidth part experiences lower latency thanthe second set of user equipment communicating with the base stationusing the second bandwidth part.
 6. The method for improving cellcoverage of claim 1, wherein the second bandwidth part provides coverageover a greater geographical area than the first bandwidth part.
 7. Acellular communication system, the cellular communication systemcomprising: a base station functioning as part of a cellular networkthat communicates with a plurality of user equipment, wherein the basestation is configured to: define a first bandwidth part and a secondbandwidth part to be implemented concurrently by the base station of thecellular network, wherein: the first bandwidth part and the secondbandwidth part do not overlap and are separated by a guard band; thefirst bandwidth part has a wider bandwidth than the second bandwidthpart; and the first bandwidth part uses a first subcarrier spacing (SCS)that is greater than a second SCS of the second bandwidth part; assign afirst set of user equipment to use the first bandwidth part and thefirst SCS for communication with the base station based on a signalstrength of each piece of user equipment of the first set of userequipment being greater than a signal strength threshold; assign asecond set of user equipment, distinct from the first set of userequipment, to use the second bandwidth part and the second SCS forcommunication with the base station based on a signal strength of eachpiece of user equipment of the second set of user equipment being lessthan the signal strength threshold; and perform communication with thefirst set of user equipment using the first bandwidth part and the firstSCS and the second set of user equipment using the second bandwidth partand the second SCS.
 8. The cellular communication system of claim 7,further comprising the plurality of user equipment, wherein a piece ofuser equipment of the plurality of user equipment is configured to:measure a signal strength of a signal received from the base station;and provide an indication of the signal strength to the base station. 9.The cellular communication system of claim 7, wherein the cellularnetwork uses 5G New Radio (NR) radio access technology (RAT) and thebase station is a gNodeB (gNB).
 10. The cellular communication system ofclaim 7, wherein the base station is further configured to: monitorbandwidth usage within the first bandwidth part and the second bandwidthpart; and reallocate a relative amount of bandwidth within the firstbandwidth part and the second bandwidth part based on the monitoredbandwidth usage.
 11. The cellular communication system of claim 7,further comprising the plurality of user equipment wherein the first setof user equipment communicating with the base station using the firstbandwidth part experiences lower latency than the second set of userequipment communicating with the base station using the second bandwidthpart.
 12. The cellular communication system of claim 7, wherein thesecond bandwidth part provides coverage over a greater geographical areathan the first bandwidth part.